Method of and means for manufacture of window-glass.



'3. L. PRINK. METHOD 0F AND MEANS FOR MANUFAGTURB 0F WINDOW GLASS. APYPLIATION FILED SEPT. 25, 1907.

941,512. Patnted Nov.3o,19o9.

2 SHEETS-SHEET 1.

n SPM# C? 9am@ R. L. FRINK.

METHOD OP AND MEANS FOR MANUPAGTURE 0Fv WINDOW GLASS. APPLICATION FILED SEPT. 25, 19'01.

941,512. l Patented Nov. 3o, 1909.

2 SHEETS-SHEET 2.

ROBERT L. ERINK; o E CLEVELAND, QHIo.

MTHOD OF AND MEANS FOR MANUFACTURE F W1'.N'I)0W-(3rLASS.v

Specification of Letters Patent.

Patented Nov. 3o, 1909.

Application tiled September 25, 1907. Serial No. 394,459.

To all 'whom it may concern:

Be itknown that I, ROBERT L. FRINK, a citizen of the United States, resident of .Cleveland, county of Cuyahoga, and State of Ohio, have invented a new and useful Improvement in Methods of and Means for the Manufacture of VVindow-Glass, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle, so as to distinguish it from other inventions.

This invenion relates to the manufacture of glass, particularly to the manufacture of colored or cathedral glass such as is used in windows, orthe like; asv will be obvious, however, the rocess and apparatus hereinafter described) are susceptible of much more general use. in the art named than that just stated.

Heretofore in the manufacture of colored glass it has been a very difficult matter to obtain definite color effect, or, in other words, a uniform mixture of the coloring substances or pigments throughout the mass of glass.

The result has been not merely an unsatis-` factory product in the particular noted, but also, due to the different co-eiiicients of expansion of the several ingredients thus.'im properly mingled, great difficulty has been experienced in producing a finished article of which the surface shall be smooth land polished. Moreover, especiall in the manufacture of Window or sheet U ass from such material, the da er of accidental and even spontaneous rupl ure due to the inherent strainfthus incurred is a source of constant trouble. These difficulties are in great measure due to the fact that the lass is ofi a viscous nature andis only miscib e at a high temperature, as also to the fact that radlation takes place atan enormous rapidity at the .temperature re uired 'to render thev metals properly miscib e.- Consequently, when, `the glass, 'as in the prevailing process, is

ladled from `the tanks where it has been melted to the vessel wherein it'is worked, the

surfaces ex osed to the air-immediately become chille and a skinv or-film of non-miscible metal is produced,` as a result of which cords tend to form in case the glass is subsequently drawn, and in any event tension.

and compression strains occur in the completed article'that tend to rupture the same even where the glass is molded or otherwise worked. In view of the foregoing considerations such manufacture of varlegated or colored glass has been a case of hit and miss both as to the production of the proper coloring eiect and as to the avoidance of internal strainsiand stresses that render the product worthless. p

The object of the present process, and apparatus for carrying on the same, is to avoid the several dificultiesin the production of the glass just named, whereby colored or' cathedral glass of a known and definite comy position, and possessed of all the desirable qualities, so far as handling is concerned,

that ordinary or clear window glass pos sesses, may be produced.

To the accomplishment of this and related ends said invent-ion then consists of the steps and the means for carrying out the same,

hereinafter fully Adescribed and specifically set forth in the claims. Y The annexed drawings and the following description set forth in detail certain means embodying the invention and one specific mode for carryingout the same, such means and disclosed mode, however, constituting but one of the various ways in which the principle of the invention may be used.

In said annexed drawings :#-Figure lrep'- resents in plan view and in moreor less diagrammatic form, a plant for the manufacture of colored or cathedral glass in accordance .with my improved process or method; Fig. 2 is a central section through one of the furnaces of such plant to ether with the parts eppur-tenant thereto; ig. 3 is a pers ective view of a measuring vessel forming a eature of such plant; and Fig. 4 is a ysection of an improved form of drawing head utilized in connection with the foregoing apparatus in the drawing of glass c linders.

Having reference t en -to the drawings just described, A shows in section, Fig. 2, a tank furnace 'of the usual type, the vcrown or cap of a second similar furnace A ap,

pearing in end. View'. In these furnaces are melted vthe necessary materials for the mak-k v ing of glass. Two or more, in the casein hand three A AfA, such furnaces are desirably located with their operative ends contiguous one tothe other and to a central point where is located a mixing vessel B. fixing vessel B is preferably supported upon a lift B', lhydraulic or otherwise, so that it ma be lowered. through the fioor of chamber .3 when desired. Access to the interior of the chamber A and to the vessel B, for pur oses of observation, or the like, is provide for by anopening a that is normally closed by means of a Swingin door a", Fior. 2. Such contiguously locate furnace ends, t ether with vmixing vessel 'B, are all desira ly Ainclosed within a common chamber As auxilia to the respective furnaces, lin `other, wor s, o ening -freely into the upper portions of their interiors and thus maintained at substantially the temperature of such furnaces.A To avoid the slight cooling effect that might be due to radiation, burners' a are desirably provided in conjunction with such chamber as shown. Such operative ends of the respec- -tive furnaces are provided with suitable ed in its normal positions to receive metal fromA the respective furnaces through the correspondin spill-ways, and mixin vessel B is so ocated with reference t ereto as to be adapted yto receive .its contents when it is oscillatedorltilted. upwardly. To faciltatethe discharge lof such contents -vessel C is furthermore pv'ided with a lip or spout a Ias shown. y ated without the chamber A is a working vessel D that has unobstructed connection with such mixing vessel. Such working vessel in the case at hand consists of a drawing pot to the details of the vstructure of which more particular attention will be called later. Such workin vessel is suitably supported in walls that, laterally inclose the same and rise "some distance thereabove. Such walls are furthermore. hollow so las to permit of the introduction of an effective heatinsulating material d such as asbestos so as to substantially entirely surround such vessel.` It is from thisworking vessel D that lthe glass is designed to be removed for op- -erative pur oses, whether in the ordinary o eration o blowing or molding, or as, in t e ca'se illustrated, to be drawn in' the form of cylinders as inthe manufacture of winy lass. The apparatus illustrated, as state relates to the drawing of cylinders in the latter connection, and is inits general features the same as that described and A above described, in a heat-insulating heat.

claimed in` m recently issued patent No. i

pot.

846,102, Marci 5, 1907. The drawingi con- ,howeveig in the case of fthe method an struction in hand, is designed on a substani tially different principle. In the description of the drawing pot in the atent just named, it has been ,consider to surround the pot bysome heatingmedium, or to apply heating means, as-gas face of the metal to the point of set has cooled chilling rings and the'like. As a result of numerous experiments I am convinced that such attempted regulation may well be dispensed with in both instances,`

since in practice the harmful effects Aaccruing therefrom far outweigh any alleged theoretical advantages. I accordingly prefer to employ a drawing-pot mounted, as

thus preventing quite completely for all practical purposes the uncertain action of radiation and convection which constitute the twolchief elements in the dissipation of The` only velement thus left, with which to deal, is conduction. By virtue of the construction adopted, loss of heat by this mode. of dissipation is yso minimized that once the pot has been raised'tothe proper temperature, it is so maintained by the continuous su ply of fresh metal from the inixingwesseljas such metal is withdrawnfronithe pot. The efects of conduction, furthermore, I would control by a suitable construction of theheat-insulating bed, particularly of that portion of the latter which rises above the level of the metal in the pot, so as to render such effects symmetrical with respect to the axis of the cylinder being drawn. Such control it is quite possible to secure, since the essentialiele-v ment to be sought therein 1s a proper proay been attempted by various ,forms of water bed,

ortioninv'of the distances between the object souo'lit to be affected and the temper-- atur wiich such object would otherwise have. WVhere, as contemplated in the construction of pot or drawing vessel illustrated means iiosentl to be describedare. i ly provided for diffusing generallyv throughout the metal in thc pot the fresh adinixture, the

disposition of the inclosing walls wherein* i it suoli pot is supported will be geonietrically symmetrical well as functionally so. lt is conceivable, however, that where diverse temperature conditions did exist in di't'- `ferent parts of the hath of nietalfroin which the cylinder is being drawn, if Such conditions were continuing and so could be .plotted as it were, a suitable deviation' from a geometrical symmetry :in the construction of the surrounding walls-would result in accomplishing the vdesired result, that of producing an equable cooling effect yuponv referred to as obtaining under normal operative conditions; this may be readily done by providing, as shown in dotted outline in Fig.

yduced from burners d3.

2, a hood or cover cl2, through apertures in which a gaseous heating blast may be intro- This cover and such external heating means have both to be removed, aside from any considerations above; discussed, in order to permit the insertion of the drawing head, presently to be described, andthe subsequent l,introductioninto the pot of the bait and the carrying o of the drawing operation.

In addition to the more or less basic change in the design of the drawing pot just considered, other changes of a minor and accessory character have also been intro! duced. Thus I construct such pot, with an exterior metal jacket d, Within which is pro-4 vided a lining Stof clay or other suitable refractory material with which alone the moltenk glass vcornes into contact. Both jacket el* and such lining d are formed on one side with an opening d that registers ,with the conduit or opening d* extending from the mixing chamber B. Such clay lin! ing d5 furthermore carries a projection d, lying directly over the opening Z7 in question, the purpose of which is to deflect down wardly the more heated metal as it flows into. the drawing-pot from the mixing vessel and thus prevent the same from rising directly to the surface. This freshv metal is thus caused to diffuse generallyv throughout the mixture in such pot and the temperature of the upper stratum from which the drawing takesplace is left undisturbed. The shell or metal jacket d* is desirably provided with means, not shown, for attaching there? to suitable lioisti,ng` means for removing or placing the t in osition as the case may 1e. ing pot and extendin lsome distance there- `above is a hollow co umn D surmounted by a head D2 around which the hollow glass article is drawn, said 'head being of a size `to substantially close the hollow article and serving asv a means to regulate the pressure between this and .thebath of metal inthe ot, all as 'is more fully set forth in said atent No. 846,102. The hollow vglass article,` or cylinder in the case in hand, is drawn of indefinite' length by means fpermitting of` the progressive changing of the poin't of ap plication of the drawing strain thereto. Such means as shown are a modification of Central y arising through said draw-v those described in my patent above referred to, in that instead of. two oppositely disposed gripping rolls having peripheral sur# y .faces of sirinf-ir character I ein lo three such rolls E disposed in triangular relation to each other. These rolls are carried, by suitable shafts e driven positively and in unison from a sin gle driving pulley c by means of gear Wheels e2 connected as indicated in 'F ig. 2. The construction of the drawinghead D2, is also modified, in that, instead of making the same of metal and so necessitating the employment of cooling means in connection therewith, as described before, I nowcon-` struct such head of clay or other refractory material and furthermore form the same with but a single peripheral flange all instead of two, the air escaping into the cylinder from'the column as before through suitable openings d provided intermediate of and. are adapted all tobe said flange and thelevel of the metal bath,y

in the pot.

Having thusdescribed, in what is thought 'sufiicient detail, the structural features characterizing my improved apparatus, I shall now briefly describe the operation ofthe same and so the general method exemplified in such operation. In such operation then, assuming thatl it is desired to make-colored or cathedral glass, measured quantities of the several vingredient metals are successively withdrawn from the respective tank furnaces A and transferred to the mixing vessels B by means of the oscillatory measurving'vessel A4 until a sufficient quantity of metal has been accumulated in vessel B to cause the level thereof inthe freelyvconnectcdworking vessel D to rise to the proper height to -permit the drawing operation vto begin.v yUpon commencement of such drawing operation as fast as the vmetal is withdrawn from the drawing pot additional measured quantities of the several ingredi ent metals are added from time vto time to the mixing vessel Bv so as to maintain thelevel of the metal at substantially the ysame height. Such successive charges of the different ingredient metals being deposited at the further end of the vmixing vessel it will be obvious that by reason of their flow therethrough and into the drawing pot they willbecome intermixed and distributed in a peculiar manner and quite automatically. Should any assistance in so mixing the mass in vessel B be required, opening as affords y a conienient means of access to the pot. Through the same opening additional ingredients' in the way of pigments or the likeiso.

hand or by machine.

viated, incidents that are practically unavoidable where extraneous, artificial, means, whoseellects are of necessity localized, are employed either to raise or lower the temperature of the material being worked.

lVhile the good results that I achieve by the several improvementsin process and apparatus hereinbefore described are particu-v larl noticeable in the manufacture of colore or cathedral lass in all its various forms, there is no lntention to limit such process and apparatus to this peculiar field. It is also to be understood that I do not confine the ap lication of the above described process to cliawing glass alone, inasmuch as in place of a Workmg Vessel'of the character described adapted for use with drawing mechanism any suitable vessel may be connected to receive the metal from the mixing vessel and the metal then withdrawn from such working vessel either for use in a molding machine or any of the other various ways in which glass may be worked, whether by Other modes of applying the principle of my invention may e employed instead of the one explained, change being made as regards theprocess herein disclosed, provided the steps or means stated by an one of the following claims or the equiva ent of such stelps or means be employed.

therefore particularly point out` and distinctly claim as my invention:-

lor cathedral,

1. The method of manufacturing colored,

or cathedral, glass, which consists in separately maintaining in molten state bodies of the several ingredient metals, and then 4 mingling such metalsapart from the work-y ing vessel. f

2. The method of manufacturing colored,

.for cathedral, glass, which consistsin separately'maintainingV in molten state bodies of the several ingredient metals, minglin such metals a art from the working vesse, and then conducting such vmetals in a combined stream to such working vessels.

3. The method of manufacturing colored, or cathedral, glass, which consists in separately maintainin in molten state bodies of the Several ingredient metals, withdrawing measured quantities of the metals from such bodies and minglingr the saine apart from the working vessel, and then conducting such metals ina combined stream to such working vessel.

4. The` method of manufacturing colored,

lass, which. consists in intermittently pouring measured quantities of the several ingredient metalsinto a mixing vess el apart from the workin r vessel;

5. The method of manu acturing colored, or cathedral, glass, which consists in intermittently pourin measured quantities of the several in e`ient metals into a 'mixin vessel apart rom the -workingvesseh and of said furnaces as desired.

then conducting such metals in a combined stream from' such mixing to such working vessel. l

6. r1"he method of manufacturing colored, or cathedral, glass, which consists'in intermittently pourin measured quantities of the several ino're ient metals into a mixing vessel apart rom the workin vessel, conducting such metals in a com ined stream from such mixing to such working vessel, and continuously -drawing the same from such working vessel'.

7. The method'of manufacturing colored, or cathedral, glass, which consists in main'- taining bodies of the several ingredient metals in a moltenstate in separate melting furnaces, and then mingling such metalsat atemperature substantially the same as that of said furnaces.

8. The method of manufacturing colored, or cathedral, glass, which consists in main-y taining bodies of the several ingredient met-als in a molten state in separate melting y furnaces, mingling such metals 4apart from! the workin vessel and at a temperature sub-` s'tantially t e same as that of said furnaces, and then conducting such metals in a combined stream to such working vessels.

9. The method of manufacturing colored, or cathedral, glass, which' consists in main` taining bodies of the several ingredient metals in avmolten state in separate melting furnaces, lwithdrawing measured quantities of the metals from such bodies and mingling the same apart from the working vessel and at a temperature substantially theA same as that of said furnaces and then conducting such metals in a combined stream to such working vessel.

1 0. `The method ofmanufacturing colored, or cathedral, glass, which consists inintermittently pouring measured quantities of the several 1n redient metals into a mixing ves?.l sel apart om the working vessel and under a temperature substantially the same as that in the melting furnace, and then conductin such metals in a combined stream from-suc mixing to such working vessel. y

11. The method of manufacturing colored, or cathedral, glass, which consists inintermittently pouring measured quantities of the` several 1n redient metals into a mixing vessel apart fiom the working vessel and underi a temperature substantially the same as thatv in the melting furnace, conducting such met- -als in a combined stream from such Amixing to such working vessel, and continuousl drawing the same from such working vesseli l2. In apparatus of the class described,4

the combination of a plurality of tank furnaces, a mixing vessel, a working vessel having connection with said mixing vessel, and means for transferring measured quantities of metal to said mixing vessel! from either vnaces, a mixin y 13. In apparatus of the class described, the combination of a plurality of tank furnaces, a mixing vessel, a Working vessel having uninterrupted connection with said mixmg vessel, d means for transferring to said inixi *essel ymeasured quantities of metal from either of said furnaces as desired.

14. ln apparatus of the class described, the' combinationfof a plurality of tank furnaces, a chamber having free communication with the' upper portion of said furnaces, a mixing vessel in said chamber, means, also wit-hin said chamber, for intermittently transferring metal to said vessel from either of said furnaces as desired, and a Working vessel located Without said chamber but connected With'said mixing vessel.

,15. In apparatus of the class described, the combination of a tank furnace, a chamber having free communication With the upper portion of said furnace, a Inixing vessel in said chamber, means, also Within said chamber, for transferring measured "quantities of metal from said furnace to said vessel, and a working vessel vlocated Without said chamber but having unobstructed connection with said mixing Vessel. y

16. In apparatus of the class described, the combination of a tank furnace, a chamber having free communication with the. upper portion of said furnace, a mixing vessel located in said chamber, an oscillatory measuring vessel for transferring metal from said furnace to said mixing vessel, a Working vessel located Without said chamber, and a conduit affording unobstructed communication between said Working and mixing vessels.

`17. In apparatus of the class described, the combination of a tank furnace, a chamber having free communication with the nippel' portion of said furnace, said furnace being provided with a spill-Way extending into said chamber, agate controlling such spill-way, a mixing vessel located in said chamber, an oscillatory measuring vessel adapted in one position to receive metal through such spill-Wai,v from said furnace and in :mother position to pour such metal intosaid mixing chamber, a working vessel located without said chamber, and a conduit affording unobstructed communication between| said working and mixing vessels.

18. In apparatus of the class described, the combination of a plurality of tank furnaces, a mixing vessel located contiguously thereto, a Working vessel having connection with said mixinor vessel, andv meansfor intermittently transferring metal from the respecltive furnaces to said mixing vessel.

19, In apparatus of the class described, the combination of a plurality of tank furvessel locatedv contiguously thereto, a wor ing vessel havin uninterrupted connection with said mixing vessel,

and means for transferring measured quantities of'metal from the respective furnaces to said lmixing vessel.

20. In apparatus for manufacturing colored, or cathedral, glass, the combination of a plurality of tank furnaces having contiguously located ends, a chamber connecting such ends and having free communication with .the interior of the respective furnaces, a mixing vessel located within said chamber, means, also Within said chambei, for intermittently transferring metal from said furnaces, respectivelyto said mixing vessel, and a Working vessel locatedjwithout said chamber but connected With said mixing vessel.

21. In apparatusfor manufacturing` colored, or cathedral, glass, the combination of a plurality of tank furnaces having contiguously located ends, a chamber connecting such ends and having. free communication with `the interior of the respective furnaces, a mixing vessel located Within said chamber, means, also within said chamber, for transferring measured quantities of metal from said furnaces, respectively, to said mixing vessel,and a Working vessel located Without said chamber but having unobstructed connection with said mixing vessel.

22. In apparatus for manufacturing colored, or cathedral, glass, the combination of a,v plurality of tank furnaces having contiguoiisly located ends, a chamber connecting "such ends and havingfree communication with the interior of the respective furnaces,

A a mixing vessel located within said chamber,

oscillatory measuring vessels, one for each furnace, for transferring metal fi'om such furnace to said mixing vessel, a Working vessel located Without said chamber, and a conduit affording unobstructed communicay tion between said Working and mixing vessels. u

23. In apparatus for manufacturing colored, or cathedral, glass,'the combination of a plurality of tank furnaces having contiguoiisly located ends, a chamber connecting such ends and havino' 'free communication with the interiors of t ie respective furnaces, each'of said furnaces being vprovided with a spill-way extending-into said chamber, gates controlling said spill- Ways, respectively, armixing vessel located in said chamber, oscillatory measuring vessels, one for each furnace, adapted in one position to receive metal thiou rh the corresponding spill- Way and in anot er position to pour such metal into said mixing chamber, a working vessel located Without said chamber, anda conduit affording unobstructed communication -beween said Working and mixing vessels. c

24. In apparatus of the class described, the combination of a plurality of tank furnaces, a mixing vesse located contiguously thereto, means for, transferring measured spective furnaces to said mixin' quantities of metal from the respective furnaces to said mixing vessel, a working vessel having connection with said mixing vessel, andmeans for drawing glass from said working vessel.

25.v In apparatus of the' class described, the combination of a plurality of tank furnaces having contiguously located ends, a chamber connecting such ends and having free communication with the interior of the res ective furnaces, a mixing vessel located wit in said chamber, means for transferring measured quantities of metal from the revessel, al working vessel located withoutsald chamber having uninterrupted connectionwith said mixing vessel; and means for continuously drawing glass from said working vessel.

26. In apparatus of the class described, the combination with a workin vessel, of a bed supporting and laterall lnclosing the same, said bed comprising eat-insulating material, whereby the heat-dissipat-ing effects of radiation and convection upon the metal in said vessel are substantially eliminated, said bed being furthermore so constructed as to render the effects of conduction upon such metal symmetrical with respect to the article being drawn.

27 .'In apparatus of the class described, the combination with a working vessel, of a record of the case in the Patent Oflice.

' [smh] bed 'supportin" and laterell nelosng -the same, said be comprising eat-insulatin material, whereby the heat-dissipating e fects of radiation and convection upon the metal in lsaid vessel are substantially eliminated, said bed furthermore rising above the level of sni'h metal and being so constructed as to renderthe ei'ects of. conduction upon Such metal symmetrical with respect to the article being drawn. A

28. The method of producing glass articles, which consists in drawing the ,same Vfrom a bath of molten glass, substantially eliminating the effects of radiation and convection upon such balth, and controlling conduction t erefrom so as to render the effects of the latter symmetrical with respect to the spect to the article being drawn.

29. The method of producing hollow glass articles, whichv consists in drawing a cylinder from a` bath of molten'glass, substan-- tially eliminating the eiects of radiation and convection upon such bath,l and controllingI conduction therefrom so as to render the effects of the latter symmetrical with respect to the article being drawn.

Signedyvby me this 28th day of August,

. ROBERT L. FRINK. Attested by- MARY ISRAEL, y J N'o. F. OBERLIN.

l It is hereby certified thatin Letters Patent N o. 941,512, granted November 30, 19.09, upon the application of-*Robert L. lFriuli, of ClevelandpOhio, fortan improvement iny Methods of andv Means for `Manufacture of Window-Glass, an error appears in the printed specification requiring correction as follows:Y Page 6, line 50, the syllable and words spect to the shouldv be stricken out; and that' thesaid Letters Patent should be read with this correction therein that the 'same may conform to the signed and sealed this met dey ef Deeember, A. D., 1909,

c. c. B1LL1NGs, Act'zg mnm-issona of Patents.

' thereto, means for, transferring measured spective furnaces to said mixin' quantities of metal from the respective furnaces to said mixing vessel, a working vessel having connection with said mixing vessel, andmeans for drawing glass from said working vessel.

25.v In apparatus of the' class described, the combination of a plurality of tank furnaces having contiguously located ends, a chamber connecting such ends and having free communication with the interior of the res ective furnaces, a mixing vessel located wit in said chamber, means for transferring measured quantities of metal from the revessel, al working vessel located withoutsald chamber having uninterrupted connectionwith said mixing vessel; and means for continuously drawing glass from said working vessel.

26. In apparatus of the class described, the combination with a workin vessel, of a bed supporting and laterall lnclosing the same, said bed comprising eat-insulating material, whereby the heat-dissipat-ing effects of radiation and convection upon the metal in said vessel are substantially eliminated, said bed being furthermore so constructed as to render the effects of conduction upon such metal symmetrical with respect to the article being drawn.

27 .'In apparatus of the class described, the combination with a working vessel, of a record of the case in the Patent Oflice.

' [smh] bed 'supportin" and laterell nelosng -the same, said be comprising eat-insulatin material, whereby the heat-dissipating e fects of radiation and convection upon the metal in lsaid vessel are substantially eliminated, said bed furthermore rising above the level of sni'h metal and being so constructed as to renderthe ei'ects of. conduction upon Such metal symmetrical with respect to the article being drawn. A

28. The method of producing glass articles, which consists in drawing the ,same Vfrom a bath of molten glass, substantially eliminating the effects of radiation and convection upon such balth, and controlling conduction t erefrom so as to render the effects of the latter symmetrical with respect to the spect to the article being drawn.

29. The method of producing hollow glass articles, whichv consists in drawing a cylinder from a` bath of molten'glass, substan-- tially eliminating the eiects of radiation and convection upon such bath,l and controllingI conduction therefrom so as to render the effects of the latter symmetrical with respect to the article being drawn.

Signedyvby me this 28th day of August,

. ROBERT L. FRINK. Attested by- MARY ISRAEL, y J N'o. F. OBERLIN.

l It is hereby certified thatin Letters Patent N o. 941,512, granted November 30, 19.09, upon the application of-*Robert L. lFriuli, of ClevelandpOhio, fortan improvement iny Methods of andv Means for `Manufacture of Window-Glass, an error appears in the printed specification requiring correction as follows:Y Page 6, line 50, the syllable and words spect to the shouldv be stricken out; and that' thesaid Letters Patent should be read with this correction therein that the 'same may conform to the signed and sealed this met dey ef Deeember, A. D., 1909,

c. c. B1LL1NGs, Act'zg mnm-issona of Patents.

Correction in Letters Patent No. 941,512.

It is hereby certified that in Letters Patent No. 941,512, granted November 30, 1909, upon the application of Robert L. Frink, of Cleveland, Ohio, for an improvement in Methods of and Means for Manufacture of Window-Glass, an error appears in the printed specification requiring correction as follows: Page 6, line 50, the syllable and words spect to the should be stricken out; and that the said Letters Pat/ent should be read with this correction therein that. the same may conform to the record of the case in the Patent Oiice.

Signed and sealed this 21st day of December, A. D., 1909.

C. C. BILLINGS, Acting mnmzlrsoner of Patente.

[SEAL] 

